Many mechanical couplings require the application of predetermined amounts of torque to screw-type fastening devices. If insufficient torque is used to tighten screws, bolts, nuts, and the like, the resulting coupling may loosen over time and fail to serve its intended application. If too great of a torque is used in tightening fasteners, then damage is often experienced, either to the fastener itself or to components being fastened. Additionally, if too great a torque is applied, difficulty in unscrewing at a later time may be experienced. Accordingly, many fastening applications are reliably accomplished only by applying a torque from within a predetermined torque range to a fastening device.
Torque wrenches are well known tools which aid in the application of predetermined amounts of torque to objects. However, torque wrenches tend to be relatively expensive and complex tools. They are often overly precise. In other words, they allow a very precisely specified torque to be applied to an object when the fastening application may not require a great precision. Generally, torque wrenches are thought of as general purpose tools that may be adapted to numerous types of screws, bolts, nuts, and the like. Moreover, conventional torque wrenches are not generally available in the population and may be perceived as being complicated to use by the general population. As a general rule, manufacturers shy away from designing mass market products which require members of the general population to use torque wrenches before the products may be used in their intended applications.
One particularly troublesome fastening application relates to the mating of common connectors used in transmitting video and similar electrical signals. Such connectors include well known connectors referred to as "F" connectors by the industry. They include a threaded nut portion that is screwed onto a mating counterpart. If such connectors are not torqued sufficiently tight, then unwanted media ingress or egress often results. On the other hand, an over-tightened connection can cause damage to the connector and/or its mating counterpart, often breaking the mating counterpart off of equipment to which it is mounted.
While an acceptable range of torque for "F" connectors is relatively wide, the cable TV industry nevertheless experiences numerous problems related to improperly tightened connections. Customers become unsatisfied and vast resources are wasted in troubleshooting reported reception problems when connections become loose. Often, customers or poorly skilled workers damage customer equipment by using conventional wrenches to apply too great a torque to the connectors. Costly repairs result.
To complicate the attachment considerations, the same connectors which should not be tightened too much when mated with typical internal or inside-located equipment should receive a greater torque when mated to external or outside-located equipment for weather proofing. Marginally skilled workers often have difficulty is appreciating this distinction and often overtighten connectors attached to internal equipment or under-tighten connectors attached to external equipment.
Conventional "F" connectors often utilize a hexagonal nut which is adapted to receive a common open-end wrench. If the connector is hand-tightened, it is seldom torqued sufficiently tight for internal or external use. If the connector is tightened with an open-end wrench, it often receives too much torque, especially when the mating counterpart is internal equipment. A less common and more expensive conventional "F" connector utilizes a round knurled nut. The knurled nut allows the application of greater hand-tightened torque when compared to the hexagonal nut style of connector. However, it is not designed to mate with a wrench and can seldom be tightened to an acceptable level for external use. Moreover, when rusting, binding, or other removal problems arise, such connectors can be exceedingly difficult to remove.